One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,5,7)(3,4,8,6)(9,10)(11,13)(12,20)(14,15)(16,18)(17,22)(19,23)(21,24)(25,26,31,28)(27,32,29,35)(30,33,38,36)(34,39,37,40)(1,3,5,8)(2,6,7,4)(10,15)(13,16)(17,20)(21,23)(27,29)(30,38)(32,35)(33,36)(1,3)(2,4)(5,8)(6,7)(10,15)(11,18)(17,20)(19,24)(25,27,31,29)(26,32,28,35)(30,34,38,37)(33,39,36,40)(1,4)(2,3)(5,6)(7,8)(9,11,14,18)(10,16,15,13)(12,19,22,24)(17,23,20,21)(25,28,31,26)(27,32,29,35)(30,36,38,33)(34,39,37,40)(9,12)(10,17)(11,19)(13,21)(14,22)(15,20)(16,23)(18,24)(25,29,31,27)(26,32,28,35)(30,37,38,34)(33,39,36,40)(9,13,14,16)(10,18,15,11)(12,21,22,23)(17,24,20,19)(25,30)(26,33)(27,34)(28,36)(29,37)(31,38)(32,39)(35,40)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.